The present application relates generally to engine start/stop controls for powertrains and more particularly, but not exclusively to engine start/stop controls for hybrid vehicle powertrains. Start/stop functionality for powertrains holds a number of potential benefits including reducing fuel consumption and mitigating emissions. Various controls schemes have been proposed for providing powertrains with start/stop functionality. While providing some benefits, existing approaches suffer from a number of drawbacks, shortcomings and disadvantages. Some approaches may result in engine start or stop operations which are undesirable in light of the state of operation of a vehicle or one or more of its constituent systems risking wear or damage to system components. Some approaches may make start/stop controls decisions resulting in significant missed opportunity for fuel savings. Some approaches fail to distinguish between operational states which appear similar based upon raw information provided to a controller, but require different start/stop controls decisions to be made if considered in the context of additional information. Some approaches are narrowly tied to particular system implementations and are insufficiently flexible and robust to apply across a broad range of engine platforms and vehicle applications. Some approaches fail to account for scenarios where an engine may be installed across a variety of powertrain platforms with differing components and needs. There remains a significant need for the unique apparatuses, methods and systems disclosed in the present application.